From the Guidelines
Labor is diagnosed when a woman experiences regular uterine contractions that cause progressive cervical dilation and effacement, with the diagnostic criteria including regular painful contractions occurring every 3-5 minutes, lasting 45-60 seconds, with progressive cervical changes (dilation and effacement) 1. The diagnostic criteria for labor are based on the presence of regular uterine contractions that cause progressive cervical dilation and effacement.
- The contractions should occur at regular intervals, typically every 3-5 minutes, and last for 45-60 seconds.
- The cervix should show signs of dilation and effacement, with the dilation increasing over time.
- The active phase of labor begins when the rate of cervical dilation increases, and this can occur at various degrees of dilation 1. Labor is divided into three stages:
- First stage (from onset of regular contractions to complete cervical dilation of 10 cm)
- Second stage (from complete dilation to delivery of the baby)
- Third stage (delivery of the placenta) Management options for labor include both non-pharmacological and pharmacological approaches, such as:
- Continuous support during labor
- Freedom of movement
- Hydrotherapy
- Breathing techniques
- Position changes
- Pharmacological pain management, including intravenous opioids like fentanyl or morphine, and regional anesthesia such as epidural analgesia 1. The most recent and highest quality study recommends that labor augmentation may be necessary if progress is slow, using oxytocin (Pitocin) starting at 1-2 mU/min and increasing by 1-2 mU/min every 30-60 minutes to a maximum of 20-40 mU/min 1. It is essential to maintain adequate hydration and nutrition throughout labor and to perform continuous fetal monitoring or intermittent auscultation to assess fetal well-being 1. These management approaches aim to ensure safe delivery while minimizing maternal and fetal complications through appropriate monitoring and interventions when necessary.
From the FDA Drug Label
Accurate control of the rate of infusion flow is essential An infusion pump or other such device and frequent monitoring of strength of contractions and fetal heart rate are necessary for the safe administration of oxytocin for the induction or stimulation of labor. The fetal heart rate, resting uterine tone, and the frequency, duration, and force of contractions should be monitored.
The diagnostic criteria for labor are not explicitly stated in the provided drug labels. However, the labels mention that oxytocin is used for the induction or stimulation of labor and that frequent monitoring of strength of contractions and fetal heart rate are necessary for its safe administration.
- Key factors to monitor include:
From the Research
Diagnostic Criteria for Labor
The diagnostic criteria for labor have been evaluated in several studies. According to a prospective study published in 2005 3, the following criteria are significant markers of the onset of labor:
- Reduction of the interval between consecutive uterine contractions
- Abdominal pain of increasing intensity
- Cervical effacement
- Cervical dilation On the other hand, backache was found to have a negative diagnostic value.
Management Options for Labor
Management options for labor can be informed by the progress of labor, which can be predicted using a biexponential model that takes into account cervical effacement, fetal station, and parity 4. This model can be used to identify abnormalities in labor progress. Additionally, the effects of individual uterine contractions on fetal head descent and cervical dilatation can be evaluated using a labor monitor based on ultrasonic triangulation 5. This can provide insights into the progress of labor and help identify potential issues.
Factors Affecting Labor Progress
Several factors can affect labor progress, including:
- Parity: Nulliparous women have slower active labor, but do not differ from multiparous women in their rate of latent labor or the cervical dilation at which they transition to active labor 4
- Fetal station: The initial fetal station can add important clinical information to labor models and help predict normal labor progress 4
- Cervical effacement: The degree of cervical effacement can affect labor progress and is a significant marker of the onset of labor 3, 4